1. Tropical Disease Research Unit (TDRU), Rajarata University of Sri Lanka, Sri Lanka.
2. Department of Community Medicine, Faculty of Medicine and Allied Sciences, Rajarata University of Sri Lanka, Sri Lanka.
3. Department of Medicine, Faculty of Medicine and Allied Sciences, Rajarata University of Sri Lanka, Sri Lanka.
4. Federal Institute for Risk Assessment, Berlin, Germany.
5. Division of Infectious Diseases, Department of Medicine, University of California, San Diego, California.